Biology today september

SEPTEMBER ’18 SEPTEMBER ’18 SEPTEMBER ’18 SEPTEMBER ’18 22 Vol XX No 63 30 September 2018 Corporate Office: Plot 99, Sector 44 Institutional Area, Gurgaon -122 003 (HR), Tel : 0124-6601200 e-mail : info@mtg.in website : www.mtg.in Regd Office: 406, Taj Apartment, Near Safdarjung Hospital, Ring Road, New Delhi - 110029 Managing Editor : Mahabir Singh Editor : Anil Ahlawat 84 42 CONTENTS 46 Bio Digest 37 51 Class XI Cell : Structure and Function 22 Check Your Vitals 30 Zoom in Bio 55 Virus Competition Edge Class XII 37 Monthly Tune Up 46 Concept Map 42 Bio Digest Evolution 51 55 63 66 69 72 73 74 75 78 79 84 85 Monthly Tune Up CBSE Drill Concept Booster Subscribe online at Individual Subscription Rates Mathematics Today Chemistry Today Physics For You Biology Today HOTS Mind Bogglers Puzzle Mania Glance Around Scientist of the Month Rapid Fire Biogram Bio Reporter Repeaters months Class XII 15 months Class XI 27 months 300 300 300 300 500 500 500 500 850 850 850 850 Combined Subscription Rates Biology Olympiad Problems You Ask We Answer www.mtg.in PCM PCB PCMB Repeaters months Class XII 15 months Class XI 27 months 900 900 1200 1400 1400 1900 2500 2500 3400 Send D.D/M.O in favour of MTG Learning Media (P) Ltd Payments should be made directly to : MTG Learning Media (P) Ltd, Plot 99, Sector 44 Institutional Area, Gurgaon - 122 003, Haryana We have not appointed any subscription agent Printed and Published by Mahabir Singh on behalf of MTG Learning Media Pvt Ltd Printed at HT Media Ltd., B-2, Sector-63, Noida, UP-201307 and published at 406, Taj Apartment, Ring Road, Near Safdarjung Hospital, New Delhi - 110029 Editor : Anil Ahlawat Readers are adviced to make appropriate thorough enquiries before acting upon any advertisements published in this magazine Focus/Infocus features are marketing incentives MTG does not vouch or subscribe to the claims and representations made by advertisers All disputes are subject to Delhi jurisdiction only Copyright© MTG Learning Media (P) Ltd All rights reserved Reproduction in any form is prohibited MT BIOLOGY TODAY | SEPTEMBER ‘18 Class XI Cell : Structure and Function This article covers high yield facts of the given topic Cell : The Basic Unit of Life • Cell is a basic membrane-bound unit that contains the fundamental molecules of life and of which all life begins • Robert Hooke was the first to observe dead cells in cork and Anton von Leeuwenhoek first saw and described live cells • Robert Brown later discovered the nucleus in the cells of orchid roots CELL THEORY • Cell theory was jointly put forward by Matthias Schleiden and Theodor Schwann in 1839 Cell theory includes following three principles: – All living organisms are composed of one or more cells – Cells are the basic units of structure and function in living beings – All cells are produced from previously existing cells TYPES OF CELLS • Cells can be mainly classified into two types on the basis of nuclear organisation: cells that have membrane bound nuclei are called eukaryotic and cells that lack a membrane bound nucleus are called prokaryotic • Cells differ greatly in size, shape and activities Mycoplasma is the smallest cell (0.15 - 0.3 µm in length) while the largest single cell is the egg of ostrich CELL STRUCTURE • Cell wall is absent in animal cell A plant cell consists of cell wall and protoplast Protoplasm includes cytoplasm and nucleus Various cell organelles like mitochondria, Golgi bodies, etc., and many cytoplasmic inclusion bodies are found in the cytoplasm • In primitive cells of prokaryotes, genetic material is not organised in the form of nucleus and other membrane bound cell organelles are also absent • Eukaryotic cells, in general comprise of following main components: MT BIOLOGY TODAY | SEPTEMBER ‘18 C-5A, 9337666760 Cell Wall Structure • It is the outer rigid, protective covering of plant cells, fungi and some protists “I not have any composed of cellulose microfibrils running through a matrix of other complex membrane and my smaller subunit is polysaccharides 40S.” • Bacterial cell wall is made up of peptidoglycan Algae have cell wall made up of cellulose, galactans, mannas and minerals like calcium carbonate • In other plants, it consists of cellulose, hemicellulose, pectins and proteins Cell wall can have three parts(i) Middle lamella - Cementing layer between the adjacent cells and is the first layer to be formed during cytokinesis It is made up of calcium and magnesium pectates (ii) Primary wall - It is formed inner to middle lamella and is capable of extension It grows by addition of materials within the existing wall (iii) Secondary wall - It is produced in mature cells that have stopped growth It is formed by deposition of materials over surface of existing structure • Plasmodesmata links the cytoplasm of adjacent plant cells in the cell wall Functions • Provides mechanical support and protection from mechanical injury • Provides shape and rigidity to the cell • Counteracts osmotic pressure and prevents bursting of plant cells by inhibiting excessive endosmosis Table : Differences between prokaryotic and eukaryotic cell Prokaryotic cell Eukaryotic cell (i) Cell is usually small Cell is comparatively larger (ii) Cell wall if present possesses muramic acid Cell wall if present, is without muramic acid Animal cells lack cell wall while those of plants and fungi possess cell wall (iii) An organised nucleus is absent, instead a nucleoid An organised nucleus is found that is differentiated into nuclear enveis found lope, chromatin, one or more nucleoli and nucleoplasm (iv) DNA is usually circular and naked, i.e., without an association (v) The amount of DNA remains the same as haploid The amount of DNA shows a regular alternation between diploid and and diploid stages are absent haploid stages (vi) Transcription and translation occur in the cytoplasm Transcription occurs in the nucleus while translation occurs in cytoplasm (vii) Cell organelles like ER, mitochondria, Golgi apparatus, lysosomes, centrioles, etc., are absent (viii) Ribosomes are of 70S type Nuclear DNA is associated with histone proteins Nuclear DNA is linear while extra-nuclear DNA is present in chloroplast and mitochondria ER, mitochondria, Golgi apparatus and lysosomes or their equivalents are present in all the eukaryotic cells Centrioles are usually present in animal cells Ribosomes are of 80S type Cell Membrane • Cell membrane or plasma membrane is quasifluid, elastic, pliable, film-like covering which surrounds the cytoplasm and also covers the cell organelles inside the cytoplasm It is semipermeable for water and selectively permeable for solutes and is made up of phospholipid bilayer Structure • The fluid mosaic model is most accepted structural model of cell membrane It was proposed by Singer and Nicolson in 1972 According to this model, there is a bilayer of lipid molecules (phospholipid) with globular protein molecules of two types - integral or transmembrane protein and peripheral or extrinsic protein and sterols which are arranged in different manner in different regions of the plasma membrane 10 MT BIOLOGY TODAY | SEPTEMBER ‘18 Scientist of the Month provided evidence basic to the modern understanding of heredity Bateson married Beatrice Durham in 1896 Towards the end of his life, Bateson came to partially accept chromosome theory, but he criticised what he perceived to be its inability to completely explain inheritance Bateson remained director at the Horticultural Institute until his death at the age of sixty-four in 1926 Contributions • In 1894, Bateson published his study of variations in the book entitled "Materials for the Study of Variation" treated with Especial Regard to Discontinuity in the Origin of Species“ He concluded that evolution could not occur through a continuous variation of species, since distinct features often appeared or disappeared suddenly in plants and animals Later on Bateson's book was considered as a landmark in biological thought • In 1900 he discovered an article, “Experiments with Plant Early life and Education W illiam Bateson was a British biologist who was born in Whitby, England on 8th August, 1861 His parents were Anna Bateson and William Henry Bateson William Henry Bateson was a classic scholar and master of St John's College at the University of Cambridge, England Bateson had five siblings After his early education in Rugby School, Bateson entered St John's College at Cambridge in 1879 Cambridge professors Adam Sedgwick and Walter Frank Raphael Weldon influenced Bateson as he studied embryology and anatomy Bateson took first class honors in natural science at Cambridge, specialising in zoology in 1883 After that, he went to U.S to work on a vertebrate ancestry project Bateson studied the morphology and embryology of the Balanoglossus kowalevskii, (later called Saccoglossus kowalevskii), under zoologist William Keith Brooks at the Chesapeake Zoological Laboratory, Johns Hopkins University, Hampton, Virginia There, Bateson observed Brooks's rejection of the traditional methods of comparative embryology and morphology to derive phylogenies After he returned to Cambridge in 1884, Bateson began publishing his research on Balanoglossus and was elected as a Fellow of St John's College in 1885 He continued his study on variation of organismal traits as part of the link between environment and adaptation, and he spent more than a year conducting related fieldwork in Russia, Turkistan and Egypt Bateson strongly advocated for Mendel's theories and he sought to expand upon Mendel's work through his own research Primarily he was criticised for that The majority of Bateson and Saunders's results from flowering plant crosses fit Mendel's laws of inheritance Bateson and his colleagues made several discoveries in genetics and described various genetic phenomena Geneticist Reginald Crundall Punnett collaborated with Bateson at Cambridge Bateson founded and named the science of genetics and his experiments 78 MT BIOLOGY TODAY | SEPTEMBER ‘18 Hybrids”, written by Gregor Mendel, an Austrian monk, 34 years earlier • In 1902, Bateson published Mendel's Principles of Heredity • Bateson and Punnett co-founded the Journal of Genetics in 1910 • Bateson and his colleagues made several discoveries in genetics and described various genetic phenomena These included Bateson's definition of linkage, the tendency of genes that are located near each other to be inherited together and epistasis, a type of gene interaction in which the expression of one gene can be activated or suppressed by another gene • Bateson demonstrated that both plant and animal populations exhibit Mendelian principles Bateson and Punnett also researched plant chimeras, single organisms that have two distinct genotypes • In 1913, Bateson published his final book, "Problems of Genetics", which discussed genetic phenomena and speciation Awards and Honours • Bateson’s work was recognised by the Royal Society in London with the award of the Darwin Medal in 1904 and the Royal Medal in 1920 He was the Society’s Croonian lecturer in 1920 • The Royal Horticultural Society awarded him the Victoria Medal in 1911 and the Royal Institution elected him as Fullerian Professor (1912-1915) • In 1912, he became chairman of Lloyd George’s important Development Commission and ten years later he was offered a Knighthood which he declined • In 1910, he received an honorary degree from Sheffield University and became an Honorary Fellow of his Cambridge College, St John's  Rapid - Revision The questionnaire contains multiple choice questions from different topics covered in this issue for effective recapitulation Vertebral formula of human is (a) C7 T11 L5 S(5) C(4) (b) C5 T12 L7 S(5) C(4) (c) C7 T12 L5 S(5) C(4) (d) C7 T10 L5 S(5) C(4) Which theory of evolution supports the evolution of short necked giraffe to long necked giraffe? (a) Lamarck's theory of inheritance of acquired characters (b) Darwin's theory of natural selection (c) Hugo de Vries mutation theory (d) Neo - Darwinism Match the Column I with Column II and select the correct option Column I Column II A Sphaerosome (i) Glycolate metabolism B Mesosome (ii) Lipid storage C Peroxisome (iii) RNA synthesis D Nucleolus (iv) Replication of nucleoid (v) Respiration A B C D (a) (b) (c) (d) (ii) (ii) (v) (ii) (v) (iv) (ii) (v) (i) (i) (i) (iii) (iv) (iii) (iv) (i) Which of the following processes takes place during diplotene stage of meiosis? (a) Recombination nodules are formed (b) The chromatids become more distinguishable (c) Tractile fibril formation occur in the region of the centromere (d) The chromosomes move towards the spindle poles along the path of their tractile fibrils Sting of bee is a modification of its ovipositor while that of scorpion is modified last abdominal segment but both have same function of defence It is due to (a) homologous organs showing adaptive radiation (b) retrogressive metamorphosis (c) analogous organs showing convergent evolution (d) atavism Enzyme succinate dehydrogenase is found in _ of mitochondria in eukaryotes (a) inner membrane (b) inner chamber (c) outer membrane (d) outer chamber Presence of different types of beaks in Darwin's finches, modified according to food habits exhibit (a) adaptive radiation (b) convergent evolution (c) parallel evolution (d) adaptive convergence Read the following statements and select the correct option (i) Amylopectin contains a large number of glucose units (ii) Inulin is used in testing of kidney function, especially glomerular filtration (iii) Husk of Plantago ovata contains mucilage which is used as stabilising and emulsifying agent in the laboratory (a) (i) and (iii) are correct but (ii) is incorrect (b) (i) and (ii) are correct but (iii) is incorrect (c) (ii) and (iii) are correct but (i) is incorrect (d) (i), (ii), (iii) and (iv) are correct Pits help in rapid translocation between two adjacent cells because (a) pit membrane consists of secondary wall (b) pit membrane is selectively permeable (c) pit membrane is permeable with minute submicroscopic pores (d) they generally occur in pairs 10 Cavity into which the head of longest and strongest bone of human body fits is (a) glenoid (b) clavicular notch (c) obturator foramen (d) acetabulum MT BIOLOGY TODAY | SEPTEMBER ‘18 79 11 Read the given differences between plant and animal mitosis and select the correct option Plant mitosis Animal mitosis The cell not change shape prior to division The cell often becomes spherical prior to division (ii) Cell plate grows centripetally Cleavage proceeds centrifugally (iii) Microfilaments not have much role in cytokinesis Microfilaments bring about cleavage (iv) Spindle is anastral Spindle is astral (i) 12 13 14 15 16 80 (a) (ii) and (iii) are correct (b) (i), (ii) and (iv) are correct (c) Only (ii) is incorrect (d) Only (iii) is incorrect Proteinoids are described as (a) organic macromolecules surrounded by film of water (b) simple organic compounds formed in Miller's experiment (c) inorganic compounds present in hot dilute soup (d) thermal polymers of amino acids Name the scientist who proposed that an organism repeats its ancestral history during its development (a) Von Baer (b) Ernst Haeckel (c) Charles Darwin (d) Lamarck Which of the following statements is incorrect? (a) 70S ribosomes are found in prokaryotes and eukaryotes (b) Free ribosomes synthesise structural and enzymatic proteins (c) 80S ribosomes are synthesised in the cytoplasm (d) Ribosomes provide enzyme peptidyl transferase Match the following and select the correct option Column I Column II A Forelimb (i) Palatine bone B Skull (ii) Calcaneum C Sternum (iii) Capitate bone D Hindlimb (iv) Manubrium (a) A-(ii), B-(iii), C-(iv), D-(i) (b) A-(iii), B-(i), C-(iv), D-(ii) (c) A-(iv), B-(ii), C-(i), D-(iii) (d) A-(iii), B-(iv), C-(ii), D-(i) Which period was dominated by plants with naked seeds? (a) Carboniferous period (b) Triassic period (c) Cenozoic period (d) Mesozoic period MT BIOLOGY TODAY | SEPTEMBER ‘18 17 18 Which of the following is a sign of parturition? (a) Fully swollen vulva (b) Mucus discharge (c) Bloated abdomen (d) All of these Identify the type of natural selection shown in the given graph Population after selection Original population 19 20 21 (a) Balancing selection (b) Progressive selection (c) Disruptive selection (d) Diversifying selection Identify the pair of vertebrochondral ribs (b) 7th and 8th (a) 8th and 9th th th (c) 11 and 12 (d) 10th and 11th Which organism possesses mammary glands but lays eggs? (a) Tachyglossus (b) Peripatus (c) Neoplina (d) Protopterus Which is correctly identified along with its feature? CH2OH H O O C H 22 H H C C C HN OH CH O=C CH N H OH H A B (a) A - macromolecule present in cell membrane (b) B - component of nucleic acid in retrovirus (c) A - component of principal energy carrier (d) B - phosphoric acid esters of nucleosides Select the correct statement (a) During dilation, the cervix gradually forces open to a diameter of approximately cm (b) Expulsion causes the baby to emerge out (c) The umbilical vessels and placenta become nonfunctional before the delivery of baby (d) None of these MONTHLY TUNE UP CLASS XII 11 16 21 26 31 36 C (b) (a) (a) (c) (c) (c) (a) (c) 12 17 22 27 32 37 (c) (b) (d) (a) (c) (b) (b) (a) 13 18 23 28 33 38 (c) (b) (b) (a) (a) (b) (c) (b) ANSWER KEY 14 19 24 29 34 39 (a) (c) (c) (a) (b) (c) (c) (b) 10 15 20 25 30 35 40 (b) (b) (d) (b) (b) (c) (b) (c) MT BIOLOGY TODAY | SEPTEMBER ‘18 81 23 24 25 26 27 Identify the meiotic stage in which a nucleolus is formed by the satellite chromosome followed by the appearance of nucleoplasm and nuclear envelope (a) Telophase I (b) Metaphase II (c) Anaphase I (d) Anaphase II Which among the following is considered as true man in human evolution? (a) Neanderthal man (b) Java ape man (c) Peking man (d) Heidelberg man Storage proteins are (a) ovalbumin, ferritin and keratin (b) glutelin, casein and collagen (c) casein, glutelin and ferritin (d) elastin, ferritin and casein A species developed in adjacent geographical area with no specific extrinsic barrier but does not mate randomly is (a) allopatric (b) sympatric (c) parapatric (d) monotypic Select the incorrect match (a) Aromatic amino acids – Phenylalanine and tryptophan (b) Acidic amino acids – Glutamic acid and asparagine ATTENTION COACHING INSTITUTES : a great offer from MTG (c) Neutral amino acids – Alanine and lysine (d) Heterocyclic amino acids – Histidine and proline 28 Which of the following enzymes is/are added to partially predigest baby foods? (a) Amylase and trypsin (b) Sucrase and amylase (c) Amylase only (d) Trypsin only 29 Projection in temporal bone of human skull is (a) odontoid process (b) mastoid process (c) coracoid process (d) olecranon process Mitotic poison(s) is/are (a) chalone (b) colchicine (c) cyanide (d) all of these 30 KEY (c) (a) 11 (c) (a) (a) 12 (d) (b) (b) 13 (b) (b) (c) 14 (c) (c) 10 (d) 15 (b) 16 (d) 21 (b) 26 (c) 17 (d) 22 (b) 27 (c) 18 (b) 23 (a) 28 (d) 19 (a) 24 (a) 29 (b) 20 (a) 25 (c) 30 (d)  CLASSROOM STUDY MATERIAL MTG “Classroom Study Material” for JEE (Main & Advanced), NEET and FOUNDATION MATERIAL for Class 6, 7, 8, 9, 10, 11 & 12 with YOUR BRAND NAME & COVER DESIGN MTG This study material will save you lots of money spent on teachers, typing, proof-reading and printing Also, you will save enormous time Normally, a good study material takes years to develop But you can have the material printed with your logo delivered at your doorstep educational publishing for JEE (Main & Advanced)/NEET/PMT Order sample chapters on Phone/Fax/e-mail  Phone : 0124-6601200 | 09312680856 e-mail : sales@mtg.in | www.mtg.in 82 MT BIOLOGY TODAY | SEPTEMBER ‘18  EXCELLEN T QUALITY CONTENT  PAPER  PRINTING MT BIOLOGY TODAY | SEPTEMBER ‘18 83 BIO -GRAM Parturition Parturition is a coordinated process of events that occur in the uterus and the fetus during last few days of pregnancy, culminating in the delivery of the infant This process majorly involves the structural changes of the cervix leading to the dilation of the cervical canal to accommodate passage for the fetus, as well as rhythmic contractions of the uterine muscle wall that are strong enough to expel the fetus Placenta Signs of Parturition Include  Umbilical cord • Bloated abdomen • Enlargement of mammary glands along with milk secretion • Fully swollen vulva and relaxed pelvic ligaments • Mucus discharge • Feeling relentlessness • Labor and strong contractions Uterus Amniotic sac Amniotic fluid Cervix Vagina Pubic symphysis Urethra Placenta Urinary bladder Vagina Cervix Rectum 9-Month-old fetus : During the last few weeks of pregnancy, as a result of everincreasing levels of estrogen, the smooth muscle cells of myometrium synthesise connexin proteins that form gap junctions between the cells, which allow the myometrium to undergo coordinated contractions Simultaneously, the cervix becomes soft and flexible due to an enzyme-mediated breakdown of its collagen fibres The cervix becomes thinner (a process known as effacement) and stretches (dilation) as the baby’s head descends and “engages” with the pelvis Ruptured amniotic sac Placenta (partially detached) Uterus Umbilical cord Third stage of birth (Placental stage) : This stage indicates the afterbirth expelling of placenta The umbilical vessels and placenta are functioning, until the delivery of the baby but within minutes of delivery, both umbilical vessels and the placental vessels completely constrict, stopping blood flow to the placenta The entire placenta becomes separated from the underlying uterine wall and a wave of uterine contractions delivers the placenta as the afterbirth 84 MT BIOLOGY TODAY | SEPTEMBER ‘18 First stage of birth (Dilation) : During this stage cervix dilates, fetus head enters true pelvis At the onset of labor or before, the amniotic sac ruptures and the amniotic fluid flows through the vagina When labor begins in earnest, the uterine contractions become strong and occur at approximately 10 to 15 minutes intervals The contractions begin in the upper portion of the uterus and sweep downward As the contractions increase in intensity and frequency, the cervix is gradually forced open (dilation) to a maximum diameter of approximately 10 cm (4 inch) Until this point, the contractions have not moved the fetus out of the uterus.  Placenta Crowning of head Second stage of birth (Expulsion) : Expulsion causes the baby to emerge out (crowning) It starts from the time of full dilation of the cervix and lasts until the baby is delivered This stage has two phases: • The initial phase is a passive (descent) phase where the baby’s head moves down through the mother’s vagina • This is followed by an active phase where the mother feels the desire to push The pushing involves contracting the abdominal muscles in time with each uterine contraction This bearing-down effort of mother may double the effectiveness of the uterine contractions to deliver the baby ZIKA VIRUS VACCINE - A PROMISING APPROACH Z ika virus (ZIKV) is a deadly, mosquito-borne flavivirus transmitted through bite of infected female Aedes mosquito It was first identified in monkeys from the Zika forest, near Lake Victoria, Uganda in 1947 The recent epidemic of ZIKV in America has revealed the catastrophic consequences of Zika infection ZIKV infection in pregnant women can lead to congenital microcephaly in newborns, i.e., small sized head and brain characterised by incomplete development of cerebral cortex It can also cause Guillain-Barre syndrome and other severe neurological disorders Although, ZIKV is primarily transmitted through the bite of an infected Aedes mosquito Other transmission modes such as sexual contact, blood transfusion and from mother to fetus are also possible Currently, there is no FDA-approved vaccine or antiviral drug for ZIKV Several efforts have been made to develop zika virus vaccine that are focussed on pre-membrane (prM) and envelope (E) protein Recently scientists have developed a methyltransferase (MTase) defective rVSV (recombinant vesicular stomatitis virus) based ZIKV vaccine platform These rVSV-based ZIKV vaccine candidates were highly attenuated but remained effective in triggering ZIKV-specific antibody and T cell immunity in mice and provided complete protection against ZIKV in mice Although, important challenges remain for the clinical development, this rVSV-based vaccine is a promising candidate for ZIKV PROBIOTICS – FRIEND OR FOE P robiotics are live bacteria that are considered good for our digestive system They are known to improve digestive health, reduce depression and promote heart health Judicious use of these probiotics is extremely important as suggested by some recent researches Immoderate use of probiotics can result in a significant accumulation of bacteria in the small intestine that can cause, brain fogginess as well as rapid, significant belly bloating as indicated by a very recent report Investigators found large colonies of bacteria breeding in the consumers’ small intestines, as well as high levels of D-lactic acid in their blood being produced by the bacteria, Lactobacillus while fermenting sugars in their food D-lactic acid is known to be temporarily toxic to the brain cells, interfering with cognition, thinking and sense of time It causes brain fogginess If brain fogginess lasts from half hour to many hours it could be very severe While probiotics can be beneficial in some scenarios, like helping a patient in restoring gut bacteria after taking antibiotics, caution is advised against its excessive and indiscriminate use Conclusively, it can be said that probiotics should be treated as a drug and not as a food supplement MT BIOLOGY TODAY | SEPTEMBER ‘18 85 86 MT BIOLOGY TODAY | SEPTEMBER ‘18 SEPTEMBER ’18 87 88 SEPTEMBER ’18 SEPTEMBER ’18 89 90 SEPTEMBER ’18 Registered R.N.I No 71810/1999 Published on 1st of every month Postal Regd No DL-SW-01/4046/18-20 Lic No U(SW)-32/2018-2020 to post without prepayment of postage N.D.P.S.O.N.D-1 on 1-2nd same month ... SEPTEMBER ’18 SEPTEMBER ’18 SEPTEMBER ’18 SEPTEMBER ’18 22 Vol XX No 63 30 September 2018 Corporate Office: Plot 99, Sector 44 Institutional... Concept Booster Subscribe online at Individual Subscription Rates Mathematics Today Chemistry Today Physics For You Biology Today HOTS Mind Bogglers Puzzle Mania Glance Around Scientist of the Month... MTG Learning Media (P) Ltd All rights reserved Reproduction in any form is prohibited MT BIOLOGY TODAY | SEPTEMBER ‘18 Class XI Cell : Structure and Function This article covers high yield facts